A study was completed to investigate the changes in fresh and hardened properties when using coarse, fractionated reclaimed asphalt pavement (FRAP) as a partial replacement of virgin coarse aggregate in a ternary blended concrete. The FRAP replacement levels were 0, 20, 35, and 50%. The ternary blended concrete consisted of 65% Type I Portland cement, 25% Grade 100 ground granulated blast furnace slag, and 10% Class C fly ash. Two coarse FRAP sources were investigated: one washed (16 mm maximum size) and one dirty (12.5 mm maximum size). The dirty FRAP source was additionally processed in the laboratory by washing and sieving over a 4.75 mm sieve to reduce the amount of fines and agglomerated sand/asphalt particles. The fresh concrete properties showed that adding FRAP had little to no effect on the air content, increased the slump, and reduced the unit weight. The fresh and hardened concrete characteristics (compressive, split tensile, and flexural strength) demonstrated that replacement levels up to 35% FRAP could be utilized without compromising existing concrete material specifications for paving. Surprisingly, washing the coarse dirty FRAP did not provide any strength benefit over the dirty, unprocessed FRAP for the sources evaluated.

Highway reconstruction consumes large amounts of energy and material resources and at the same time produces significant quantities of emissions during material processing, transportation, and site construction. Sustainable highway reconstruction requires strategies that optimally utilize recycled or virgin material from supply locations (e.g., existing roadway, material markets), assign material use in reconstruction process, select fixed staging area(s) and mobile unit location(s) to process material, and ship the material to the destinations (e.g., markets, landfills, highway construction sites). We present a decision support system based on a network optimization model that determines (i) optimal locations of fixed staging areas and mobile processing units and (ii) optimal material recycling and shipment strategies that minimize the total cost for material procurement, transportation, staging area and mobile processing unit investment, and CO2 equivalent (CO(2)e) emissions. A hypothetical case study of a 35-mile reconstruction project was conducted to test the performance of the model and to draw insights on how different system parameters influence the optimal staging locations, recycled material use, and traffic management plan. It was found that the use of mobile processors and/or recycled material can have significant impacts on hauling costs, emissions, and optimal locations of staging areas.